Gib and cotter bolt assembly



Aug. 31, 1965 A.-J.-ROUBAL 613 AND (POTTER BOLT'ASSEMBLY Filed May 5,1962 3 .J/ M A E 4 .MJ 2 x 9 2 T2 5 5 w My m. 2 mm 7 6 \L United StatesPatent 3,203,548 GIB A'ND (TO'ITER BOLT ASSEMBLY Alexander J. Roubal,Milwaukee, Wis., assignor to Allis- Chalmers Manufacturing Company,Milwaukee, Wis. Filed May 3, 1962, Ser. No. 192,197 1 Claim. '(Cl.209-399) This invention relates to gib and cotter bolt assemblies andparticularly to such assemblies that may be used for such as holdingdown decks or tensioning cloths in vibrating screens or similarequipment.

While cotter bolt assemblies are used in many different types ofapplications, a common usage is as a fastening or tensioning deviceWhere periodic removal is necessary. The cotter boltassembly findsadvantageous usage in these types of applications primarily because ofthe speed and simplicity of assembly and disassembly.

Prior to this invention it was necessary for many users of cotter boltsto stock a large number of different length sizes. This was necessaryfor several reasons. One reason was that various sizes were necessarybecause of the varied sizes of machines in which the wedge boltassemblies were used. Another reason stocks of different size bolts werenecessary was because the use of the wedge bolt assembly in such astensioning devices required a periodic tightening as the tensionedmaterial stretched from its initial dimensions beyond that which couldbe remedied by the tightening allowed by further insertion of the wedge.When a cotter could be driven no further into the cotter way, it wasnecessary to remove the entire cotter bolt assembly and replace it withan assembly of shorter effective length so the desired tension could beprovided.

An object of the present invention is to provide a cotter bolt assemblythat can be incrementally adjusted to provide variations in itseffective length without removing the cotter bolt from structure inwhich it is mounted.

Another object of this invention is to provide a cotter bolt assemblythat will function properly, even in a vibrating structure, at any anglethat it may protrude through framework structure.

This invention accomplishes the stated objects by providing in a cotterbolt, a cotter way that receives not only the cotter but also receives agib of unique design and function. The gib is movable or rotatable aboutan axis perpendicular to both the shaft and the cotter way so thatvarious selected positions of the gib determine different effectivelengths of the bolt. Thus, a simple movement of the gib extends therange of tensions that a single size cotter bolt can apply to such asthe cloth deck of a vibrating screen and without any change of parts.

Different size gibs may, of course, be stocked for utilization with asingle size cotter and bolt to even more greatly vary the effectivelength of such assemblies and to do so will also be less expensive thanstocking many sizes of cotter bolts. To enable the cotter bolt assemblyto securely hold together with little regard to the angle between thecotter and the axis of the bolt, the outer surface of the gib that comesin contact with the cotter is of a continuous curved nature, such as anouter edge of a thin and flat C-shaped gib, so that at whatever anglethe bolt assumes to the cotter, the nature of the contact between thecotter and the gib is always essenially the same, i.e., a curved surfaceof the gib engaging a flat surface of the cotter.

Other features and objects of the invention that have been attained willappear from the following more detailed description of the inventionwith reference to the accompanying drawings, in which:

FIG. 1 is a fragmentary view of a vibrating screen illustrating a cotterbolt and gib assembly embodying this 3,203,548 Patented Aug. 31, 1965invention, with the bolt of the assembly extending through framework ofthe screen;

FIG. 2 is a top view of a cotter bolt that may be utilized in thisinvention;

FIG. 3 is a plan view of the gib shown in FIG. 1; and

FIGS. 4, 5 and 6 are side views of the cotter bolt, partly in section,and showing the gib in three positions to vary the effective length ofthe cotter way and hence the effective length of the bolt itself.

Referring to FIGS. 1 and 2, there is shown a portion of a screen of suchtype as is used for example to dewater material or to separate coarsefrom finer particles by passing the material over a screen deck 1 whichmay be a perforated plate or meshed fabric. The deck may be positionedas shown by side panel 2 that has upper and lower portions, 2a and 211,respectively, angled with respect to the panel 2 for purposes that willappear as this description proceeds. The panel 2 is arranged within aframe 3 and mounted thereto in a manner that will be explained, Abracket 4 is attached to framework 3 and the bracket defines a channel 5and portion 2a of panel 2 projects into channel 5 to engage bracket 4.Lower portion 2b of panel 2 engages the deck 1 to hold it down or whendeck 1 is a fabric, portion 2b may engage the fabric so that a pivotalmovement of panel 2 relative to bracket 4 in the direction that bringsportion 2b closer to frame 3, acts to pull deck 1 tight and smooth. Whensuch pulling on deck 1 to apply tension thereto is desired, a bracket 6may be secured to deck 1. Bracket 6 defines a channel 7 and portion 212of panel 2 projects into channel 7 to engage bracket 6 so that thepivotal movement of panel 2 can tension deck 1.

A pivotal motion is imparted to panel 2 by an assembly 10 that includesa cotter bolt 11 having a cotter way 12. The cotter bolt 11 passesfreely through a hole in panel 2 and a head portions 13 on the inner endof the bolt engages the panel. The cotter way 12 is defined by a pair ofend walls 14, 15 and a pair of side walls 16, 17 (see FIG. 2). A gib 20thinner than the width of cotter way 12 is inserted in cotter way 12 ina manner that will be described later. A cotter 30 is inserted intocotter way 12 between the gib 20 and frame 3.

Referring to FIG. 3, the gib 20 is shown as having a C-shaped outer edge21. The C-shape is defined by three principal portions, a cap 22, atrunk 23, and a foot 24. These three portions have straight inner edges25, 26, 27, respectively, that are unequal radial distances from theouter edge 21.

Referring again to FIG. 1, the gib 20 is shown arranged with innerstraight edge 26 of the trunk portion 23, engaging end wall 15. Thecotter 30, which is inserted in cotter way 12 between gib 20 and frame3, is driven downwardly to move the bolt 11 to the left as shown inFIG. 1. Such movement by bolt 11 will pull panel 2 to pivot the panelclockwise about bracket 4 and panel 2 will push down on deck 1 or whendeck 1 is a fabric with, as shown, a bracket 6, the clockwise motion ofpanel 2 will tension the deck 1.

The manner in which gib 20 can be used to vary the effective length ofcotter way 12 will be explained with reference to FIGS. 4, 5 and 6.

As shown in FIG. 4, cap portion 22 of the gib 20 is arranged in cotterway 12 with edge 25 in engagement with end wall 15 thus reducing theeffective length of cotter way 12 from the distance between walls 14, 15to the distance X between cap portion 22 and wall 14. The manner, inwhich a further reduction in the effective length of cotter way 12 canbe achieved, is illustrated in FIG. 5.

As shown in FIG. 5, trunk portion 23 of the gib is arranged in cotterway 12 with edge 26 in engagement with end wall 15. Thus the eifectivelength of cotter way 12 is reduced from the distance X shown in FIG. 4,to the distance Y in FIG. 5, between trunk portion 23 and wall 14. Themanner in which a still further reduction in the effective length ofcotter way 12 can be achieved is illustrated in FIG. 6.

As shown in FIG. 6, foot portion 24 of the gib is arranged in cotter way12 with edge 27 in engagement with end wall 15. Thus the effectivelength of cotter way 12 is reduced from the distance Y shown in FIG. 5to the distance Z in FIG. 6 between foot portion 24 and wall 14. Thusthe unique configuration of the gib shown in FIG. 3 provides forsubstantial variationin the effective length of cotter way 12 and theutility of any size cotter bolt and cotter is considerably broadened.

Still another unique feature of the gib shown in FIG. 3 is the provisionof lip portions 28, 29 that project toward each other from cap portion22 and foot portion 24 to define a space therebetween that is shorterthan the length of edge 26 and the space between edges 25, 27. Theparticular utility of lips 28, 29 may be best understood with referenceto FIGS. 4 and 6. FIG. 4 shows gib 20 arranged with lip 28 hooked underbolt 11 to resist any otherwise possible tendency for the gib 20 to popout of cotter way 12, when such an assembly is applied to a vibratingscreen in an arrangement exemplified in FIG. 1. FIG. 6 shows gib 20arranged with lip 29 hooked over bolt 11 to resist any otherwisepossible danger that the gib might be driven through and out cotter way12 when the cotter is driven into the space 12 between foot portion 24and wall 14,

From the foregoing it can be seen that the described gib,gib-cotter-bolt assembly, and gib-cotter-bolt screen assembly are eachpossessed of unique advantages. However, modifications and equivalentssuch as readily occur to those skilled in the art are intended to beincluded within the scope of this invention and thus the scope of theinvention is intended to be limited only by the scope of the claimappended hereto.

Having now particularly described and ascertained the nature of my saidinvention and the manner in which it is to be performed, I declare thatwhat I claim is:

In a vibratory apparatus having a frame, a panel within said frameconnected to said frame for pivotal motion relative thereto, a cotterbolt having a cotter way extending therethrough, said cotter boltengaging said panel and projecting out through said frame to an extentthat places a portion of said way on the side of said frame oppositesaid panel, a cotter in said way and engaging the side of said frameopposite said panel, and a gib in said way between said cotter and anouter end wall of said way, said gib having a continuously curvedC-shaped outer edge surface and cap, trunk and foot portions each havingan inner flat surface a different distance from the outer edge surface,each of said inner fiat surfaces being selectively engageable with saidouter end wall, and each of said inner surfaces upon engagement withsaid outer end wall presenting a different portion of said outer edgesurface of said C-shaped gib to engage said cotter a different distancefrom said outer end wall, and the ends of said cap and foot portionsremote of said trunk portion each having lip portions spaced apart fromeach other a distance less than the remainder of the cap and footportions to insure said gib remaining in place between said cotter andsaid outer end wall.

References Cited by the Examiner UNITED STATES PATENTS 597,143 1/98Everitt 209-403 1,371,396 3/21 Reveny -7 1,461,195 7/23 Meyer 85-71,737,091 11/29 Northey 857 2,514,965 7/50 Pierre 248354 2,813,629 11/57Brugmann 209-403 FOREIGN PATENTS 1,115,205 10/60 Germany.

685,024 12/52 Great Britain.

HARRY B. THORNTON, Primary Examiner.

EDWARD 1. MICHAEL, Examiner.

